A holobook was a slim, crystalline board which was used to store vast amounts of information. Holobooks were incredibly durable and required only a small amount of power to remain active. The Jedi Archives, located on Coruscant during the last decades of the Galactic Republic, contained millions of holobooks, some of which dated back to the origins of the Republic. When properly stored and maintained, holobooks gave off a soft, light blue glow. Like the Jedi Holocrons, holobooks provided interactive interfaces to their knowledge, allowing a reader to delve as deeply into subject matter as they desired.